A sort of BSA

[Greybeard]

Another Facebook scrape:

Geoff Stray says, "This is my 'Evans BSA'. The bike was originally developed between 1984 and 1998. Engineer Owen Evans designed and built the engine over 4 years from 84 to 88. It was covered in magazine articles in 1988 and 1995. I got hold of it after it had been under a tarp for 18 years. Only the top ends are BSA (B50) - the rest is Norton Dominator and Norton Commando. It does go rather well though. The crankcases and crankshaft were handmade; ccm camshafts and oil pump (modified); no decompressors - so compression ratio had to be reduced slightly  to about 9.5:1 to render starting just possible."

https://youtu.be/-C3OlhFx7Q8

[RDfella]

Neat job, but can't help thinking the exhausts would look so much neater if they were 2 into 1.

[Greybeard]

...can't help thinking the exhausts would look so much neater if they were 2 into 1.

They sort of go 2 into 1 into 2

[RoyC]

...can't help thinking the exhausts would look so much neater if they were 2 into 1.

They sort of go 2 into 1 into 2

It's an X pipe, done to scavenge the gasses out of the cylinders.

https://www.youtube.com/watch?v=Dd43rwLHEW4